R10 Mk2 fill valve check ball help needed.

[matchman]

 I dis assembled the fill valve the chec k portion that prevents the air from exhausting when the probe is removed.(threaded brass housing/ spring/follower/o ring seal) I never seen a check ball . I assumed I lost it. (Poor eyes) Watched U tube vids and one is shown. I acquired a ball and reassembled and cannot fill it. Removed ball and all is fine.
After much looking on the net I found 1 comment that there was a version that did not use a check ball. Is this true? (The spring guide is shaped like a piston and this seals the o-ring)
Thanks for any help.